Timer计时不准确的解决方案 每次都重新调整，修正误差

http://stackoverflow.com/questions/29722838/system-timers-timer-steadily-increasing-the-interval

需要在计时器每次运行后，修正计时器的间隔

通过DateTime的Tick来处理

public class Meter
    {
        private Timer ReadingTime;
        private DateTime NextTickTimeWholeSeconds;

        public Meter()
        {
            DateTime now = DateTime.Now;
            NextTickTimeWholeSeconds = new DateTime(now.Ticks - (now.Ticks % TimeSpan.TicksPerSecond), now.Kind);

            ReadingTime = new Timer();
            ReadingTime.Elapsed += new ElapsedEventHandler(PerformReading);
            ReadingTime.Interval = GetTimeToNextSecond();
        }

        public void StartMeter()
        {
            ReadingTime.Start();
        }

        public void StopMeter()
        {
            ReadingTime.Stop();
        }

        private double GetTimeToNextSecond()
        {
            NextTickTimeWholeSeconds = NextTickTimeWholeSeconds.AddSeconds(1);
            var interval = NextTickTimeWholeSeconds - DateTime.Now;
            return interval.Milliseconds < 1 ? GetTimeToNextSecond() : interval.Milliseconds;
        }

        /// <summary>
        /// 定时处理
        /// </summary>
        /// <param name="sender"></param>
        /// <param name="e"></param>
        private void PerformReading(object sender, ElapsedEventArgs e)
        {
            Console.WriteLine(DateTime.Now.ToString("yyyy-MM-dd HH:mm:ss.fff"));
            //Console.WriteLine("Performing reading: " + DateTime.Now.Hour + ":" + DateTime.Now.Minute + ":" + DateTime.Now.Second + "." + DateTime.Now.Millisecond);
            ReadingTime.Interval = GetTimeToNextSecond();
        }
    }